Health authorities in Queensland have declared a "first in the world" strain of the Omicron variant has been discovered as leaders continue to mull over a response to the evolving pandemic.
The national cabinet will meet on Friday to coordinate responses to the new Covid-19 variant as mystery surrounds the potency of the strain.
Queensland will fling open its borders to interstate travellers on Monday, but Health Minister Yvette D'Ath warned the discovery was further evidence policies would need to be flexible.
Queensland recorded no new community cases on Wednesday but two Omicron infections previously detected in hotel quarantine in Cairns and Brisbane had been reclassified following the scientific development.
Victoria also recorded its first case of Omicron on Wednesday.
The new variant was detected in a traveller who arrived in southeast Queensland from South Africa, which D'Ath said had been named by the World Health Organisation as "Omicron-like".
"I want to give a huge thank you to our forensic scientific services," she said.
"It is their work with the international committee that has led to the international committee reclassifying Omicron into two lineages and we have both of them here in Queensland.
"This is a new variant," the Health Minister told reporters on Wednesday morning.
"Remember, it's only been days since this has become an issue for Australia and other countries.
"And now, today, we are standing here announcing a new version of Omicron and it's a first in the world."
Acting chief health officer Dr Peter Aitken described the discovery as "amazing work" which would improve testing capabilities and the identification of more destructive variants.
"They have picked up the differences here, worked through it in a methodical and scientific approach, and recognised there are differences between the full and normal Omicron classification.
"The important part is that those two sub-lineages — one has the S-gene dropout, which we've talked about and is the normal means of screening for Omicron, and this other strain doesn't have the S-gene dropout.
"It's going to lead to improvements in people recognising the potential spread of Omicron in all communities."
Aitken said it was too early to determine the severity of the Omicron variants but warned the virus was becoming more easily transmissible.
"We don't know enough about it as far as clinical severity, vaccine effectiveness," the acting top doctor said.
"What we do know is that Omicron is more infectious and more transmissible.
"We now have Omicron and Omicron-like — it's a reminder to us all that as we open our borders this doesn't mean that the Covid journey has finished, in many ways the Covid journey is just starting."
The case in Cairns who arrived from Nigeria has the other strain of Omicron, with all passengers who shared the flight now deemed close contacts.
Those who have received both doses of the vaccine and with evidence of a negative test within 72 hours of entry will be welcomed into Queensland from interstate hot spots on December 13.
More than 79 per cent of Queenslanders have received both doses of the Covid-19 jabs, while 87.5 had received a single dose.